The discrete differential operators are defined on the graph based on nonlocal methods [1]}, [2]}, [3]}. First, we define the nonlocal gradient operator \(\nabla _w\)  acting on \(\mu _i\)
\( {\nabla _w}{\mu _{i}} \triangleq \left( {{\mu _j} - {\mu _i}} \right)\sqrt{{w_{ij}}} {\text{ }} :V \rightarrow \mathbb {R}.\) 
